<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <script src="https://cdn.jsdelivr.net/npm/vue@2.7.14/dist/vue.js"></script>
  <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@4.6.2/dist/css/bootstrap.min.css" integrity="sha384-xOolHFLEh07PJGoPkLv1IbcEPTNtaed2xpHsD9ESMhqIYd0nLMwNLD69Npy4HI+N" crossorigin="anonymous">
  <style>
    .red{
      color: red;
    }
    </style>
</head>
<body>
  <div id="app">
    <div class="container">
      <!-- 顶部搜索框模块 -->
      <div class="form-group">
        <div class="input-group">
          <h4>品牌管理</h4>
        </div>
      </div>
      <!-- 添加资产 -->
      <form class="form-inline">
        <div class="form-group">
          <div class="input-group">
            <input
            type="text"
            class="form-control"
            placeholder="资产名称"
            v-model.trim="name"
            />
          </div>
        </div>
        &nbsp;&nbsp;&nbsp;&nbsp;
        <div class="form-group">
          <div class="input-group">
            <input
            type="text"
            class="form-control"
            placeholder="价格"
            v-model.number="price"
            />
          </div>
        </div>
        &nbsp;&nbsp;&nbsp;&nbsp;
        <!-- 阻止表单提交 -->
        <button class="btn btn-primary" @click.prevent="add">添加资产</button>
      
      <!-- 数据表格 -->
      <table class="table table-bordered table-hover mt-2">
        <thead>
          <tr>
            <th>编号</th>
            <th>资产名称</th>
            <th>价格</th>
            <th>创建时间</th>
            <th>操作</th>
          </tr>
        </thead>
        <tbody v-if="list.length > 0">
          <tr v-for="item in list" :key="item.id">
            <td>{{ item.id }}</td>
            <td>{{ item.name }}</td>
            <td :class="{ red: item.price > 100 }">{{ item.price }}</td>
            <td>{{ dayJs(item.time) }}</td>
            <!-- 如果价格超过100，就有red这个类 -->
            <td><a href="#" @click.pervend="del(item.id)">删除</a></td>
          </tr>
          
          <tr style="background-color: #EEE">
            <td>统计</td>
            <td colspan="2" >总价: {{ allPrice }}</td>
            <td colspan="2" >均价: {{ avgPrice }}</td>
          </tr>
        </tbody>
        <tfoot v-else>
          <tr>
            <td colspan="5" style="text-align: center">暂无数据</td>
          </tr>
        </tfoot>
      </table>
      
      </form>
    </div>
  </div>
  <script src="https://cdn.bootcdn.net/ajax/libs/dayjs/1.11.7/dayjs.min.js"></script>
  <script>
    const app = new Vue({
      el: '#app',
      data: {
        name: "", // 名称
        price: '', // 价格
        list: JSON.parse(localStorage.getItem('list'))
        // list: [
        //   { id: 100, name: "外套", price: 199, time: new Date('2010-08-12')},
        //   { id: 101, name: "裤子", price: 34, time: new Date('2013-09-01') },
        //   { id: 102, name: "鞋", price: 25.4, time: new Date('2018-11-22') },
        //   { id: 103, name: "头发", price: 19900, time: new Date('2020-12-12') }
        // ]
      },
      methods: {
        add() {
          if (this.name === '') {
            return alert('请输入商品名字')
          }
          if (typeof this.price !== "number") {
            return alert('请输入商品价格')
          }
          this.list.push({
            id: this.list.length + 1 ,
            name: this.name,
            price: this.price,
            time: + new Date()
          })
        },
        del(id) {
          this.list = this.list.filter(item => item.id !== id)
        },
        dayJs(){
          return dayjs().format('YYYY-MM-DD HH:mm:ss')
        }
      },
      computed: {
        allPrice() {
          return this.list.reduce((sum, item) => sum += item.price, 0)
        },
        avgPrice() {
          return (this.allPrice / this.list.length) || 0
        }
      },
      watch: {
        list: {
          deep: true,
          immediate: true,
          handler() {
            localStorage.setItem('list', JSON.stringify(this.list))
          }
        }
      }
    })
    </script>
</body>
</html>